Obsidian Sync

Obsidian is a note-taking and personal knowledge management application by Obsidian.md that stores notes as local Markdown files. It provides features for linking notes (backlinks), a graph view, and a plugin system for extensibility across desktop and mobile.

Syncular is an offline-first SQL synchronization toolkit that keeps an SQLite database on each client while treating a server-owned commit log as authoritative. Applications read and write local SQLite immediately; writes enter an outbox and are checked and reconciled by the server during synchronization. The browser client runs SQLite on OPFS, while native integrations share a Rust core with native SQLite through bindings for Rust, Swift, Kotlin, Flutter, React Native, and Tauri. Servers can run on Bun, Node, or Cloudflare Workers with SQLite, Postgres, or D1. The project also provides server-side persistent SyncClients, database-less SyncRemoteClients, schema and query code generation, React hooks, column encryption, Yjs CRDT integration, and TypeScript and Rust implementations checked against a shared conformance catalog. Syncular is maintained by Benjamin Kniffler and is pre-1.0; its public APIs and protocol details may change before 1.0. The repository is released under the license stated in its repository files.

Dropbox is a cloud storage and file sharing service operated by Dropbox, Inc. It provides file synchronization, personal cloud, desktop and mobile clients, and collaboration tools for individuals and businesses. The company was founded in 2007 by Drew Houston and Arash Ferdowsi and completed its initial public offering in 2018.

Whalesync is a data synchronization platform that provides two-way syncing between databases and productivity apps. It connects sources such as PostgreSQL, Airtable, Notion and others to keep records synchronized across systems for application backends and operational workflows.

BookOrbit is a self-hosted library and reading platform for ebooks, PDFs, audiobooks, and comics. It provides web readers and synchronizes reading progress, highlights, annotations, and reading status between BookOrbit, Kobo devices, and KOReader. The platform includes library management with metadata enrichment, multiple libraries, collections and rule-based saved filters, multi-user accounts with OIDC/SSO, OPDS access, Send-to-Kindle delivery, and browser uploads. It also provides reading statistics, goals, achievements, searchable annotation exports, and synchronization with services including Hardcover, Readwise, and StoryGraph. The project is designed to run on infrastructure controlled by the operator.